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Ok,

Since Ive been looking into an amp for my car Ive been noticing a LOT of funky business. Truth be told I havent been really looking at amp specs in about 8-10 months really.

Im seeing stuff like this:

RMS Power Output:
* 450 watts, Punch Series 4-Channel Amplifier
* 4 Ohms: 60 watts RMS x 4 chan.
* 2 Ohms: 110 watts RMS x 4 chan.
* 4 Ohms Bridged: 225 watts RMS x 2 chan.

Now back in "the day" when you had 60 WRMS x 4 channels @ 4 Ohm, when you bridge them channels it would then be 120 WRMS x 2 channel @ 4 Ohms.

So it leads me to wonder if these new ratings are making things even more deceptive than before, or is there some new mircale amp topology I never noticed?

I guess they really mean the 225 WRMS x 2 @ 4 Ohms as its rated @ 450 WRMS total...

Either that or Im just so F'ing tired I cant think str8...

an exert from our ampilifier faq

"If we had our perfect amplifier, upon bridging it we would have a single channel amplifier with exactly four times as much power as any one channel of the amplifier in "normal" stereo mode, assuming a 4 ohm speaker load. "

take smoker's elevation amp he's selling for example.... 125 x 4 @ 4 ohm. 500 x 2 @ 4 ohm

Hehe,

I was just watching a Movie and was thinking about this thread. I realized what I was failing to think of earlier

Now that its time to go to bed, well I think Im finally waking up!

Not the new CEA rating or new amp topology, just tiredness clouding the mind :happy055:

Not to self, get at least 5 hours of sleep before speaking publicly again

lol it happens...

two4fifteen wrote:lol it happens...

Yeah, just look at my post from a couple days ago... I was saying amp instead of alt

Ya it just bugged me.

Yesterday was just a very dopey day for me, lol and rightfuly so.

I feel kind of embarassed about that post but am going to leave it as a reminder to all, even us mods have bad/stupid days.



Its a good thing I didnt buy an amp yesterday like I about did. WOuld of made som BAD choices...

RF is correct. This is the way it's always been.
60x4@4ohms =
120x4@2ohms=
240x2@4ohms bridged

bridging the channels gives the same combined power at 4 ohms as you have in stereo at two ohms, where in this case stereo is all 4 channels.

Lol,

ya yesterday it took me a few hours to remember that.

Bad day, you come back lata you hear?

did anyone else notice glass's little error whilst "straightening out" ryan...

It mainly depends on how regulated the power supply is.
Or, could be the result of stressing the power supply enough to sag.

A completely unregulated power supply would result in a true 120x2 at 2 ohms, from an amp that was 60x2 at 4 ohms.

A very tightly regulated power supply could result in an amp that wasn't much higher than 60x2 even at 2 ohms.

With a power difference like this though, I don't suspect a regulated power supply, I suspect a saturated (read: stressed) power supply.

I thought you were going to complain about RF's habit of publishing certain "rated" specs for their amps, then including birthsheets that admittedly don't conform to rated numbers (ie distortion spec ">" is circled ) with wild, way-up-there power numbers to make people feel like they got "a more powerful amp" than rated.